This application is based on Patent Application No. 2000-296575 filed in Japan, the content of which is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to photographic art, and specifically relates to photographic art used by portable terminals such as portable telephones, personal digital assistants (PDA) and the like.
2. Description of the Related Art
It has become practical to provide an integrated or removable camera element for photography in portable terminals such as portable telephones, PDAs and the like, making it possible to transmit not only mutual voice information but also image information such as mutual display information when communicating remotely.
Using such a portable terminal may be inconvenient for a user, however, when photographing an object in the very near distance from the portable terminal due to the difficulty in achieving an appropriate focus.
Furthermore, when changing photography magnification using a photographic optical system having a zoom function for changing in steps the photography magnification by independently driving a plurality of lens units, there is often a mismatch in timing by which the respective lens units reach a position corresponding to each photography magnification. This situation is inconvenient because it takes a longer time to focus due to the generated focus divergence.
One object of the present invention is to provide a highly convenient portable terminal and drive method for a photographic optical system.
One aspect of the present invention is a portable terminal comprising an image pick-up element for acquiring an object image, a photographic optical system for forming an object image on the image pick-up element, and a moving mechanism for moving or modifying the structure, i.e., the position of the photographic optical system for macro photography.
Another aspect of the present invention is a portable terminal comprising an image pick-up element for acquiring an object image, a photographic optical system for forming an object image on the image pick-up element, and a focusing mechanism for moving or modifying the structure, i.e., the position of the photographic optical system for macro photography and setting an in-focus state.
Yet another aspect of the present invention is a driving method for driving a plurality of lens units comprising setting a first position of each lens unit for a first photography magnification, and setting a second position of each lens unit for a second photography magnification, and independently driving each lens unit to modify the photography magnification from the first photography magnification to the second photography magnification, in which setting the respective moving speeds of lens units in accordance with the moving distance of each lens unit moving from the first position to the second position, and driving each lens unit at the moving speed of the respective lens unit.
Still another aspect of the present invention is a driving method for driving a plurality of lens units comprising setting a first position of each lens unit for a first photography magnification, and setting a second position of each lens unit for a second photography magnification, and setting a third position of each lens unit for a third photography magnification, and independently driving each lens unit to modify the photography magnification from the first photography magnification through the second photography magnification to the third photography magnification, in which driving each lens unit from the first position to the second position, stopping the movement of a lens unit that reaches the second position, and driving each lens unit from the second position to the third position after all lens units have arrived at the second position.
These and other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings, which illustrate specific embodiments of the invention.